The present invention relates to marine drive systems; and more particularly, the invention relates to the drive and gearing of two propellers for a ship.
The U.S. Pat. No. 3,881,444 (see also German printed Patent Application 21,34,972) describes a gear transmission for a pair of marine propellers in which each propeller has its own shaft, and an intermediate shaft is geared to the respective propeller shaft. Moreover, a separate turbine with a clutch is provided for each gear; but interconnecting gearing couples the two intermediate shafts to each other to obtain synchronization. The system is, moreover, constructed in such a way that one turbine can, if necessary, drive both propellers. This mode of operation can be used, e.g., for slow-speed cruising, while high-speed propulsion requires running of both turbines.
German Pat. No. 21,87,237 describes also a two-propeller, two-turbine system and a connection which also runs always when both of the two turbines run, so that here, too, the connecting transmission consumes power.